Summary

We characterised the adherent cell types isolated from human skeletal muscle by enzymatic digestion, and demonstrate that even at 72 hours post-isolation these cultures consist predominantly of myogenic cells (CD56+, Desmin+) and fibroblasts (TE-7+, Collagen VI+, PDGFRα+, Vimentin+, Fibronectin+). To evaluate the behaviour of the cell types obtained, we optimised a double immuno-magnetic cell sorting method for the separation of myogenic cells from fibroblasts. This procedure gave purities of >96% for myogenic (CD56+/desmin+) cells. The CD56- fraction obtained from the first sort was highly enriched in TE-7+ fibroblasts. Using quantitative analysis of immunofluorescent staining for lipid content, lineage markers and transcription factors, we tested if the purified cell populations could differentiate into adipocytes in response to treatment with either fatty acids or Adipocyte Inducing Medium. Both treatments caused the fibroblasts to differentiate into adipocytes, as evidenced by loss of intracellular TE-7, upregulation of the adipogenic transcription factors PPARγ and C/EBPα, and adoption of a lipid-laden adipocyte morphology. In contrast, myogenic cells did not undergo adipogenesis and showed differential regulation of PPARγ and C/EBPα in response to these adipogenic treatments. The data show that human skeletal muscle fibroblasts are at least bipotent progenitors, capable of remaining as extracellular matrix-producing cells or differentiating into adipocytes.

Pavan Vedula and Anna Kashina propose a new concept, the actin code, which encompasses the regulation of the essential functions of mammalian actins at the nucleotide level, rather than at the level of amino acids.

“To me, there are no real boundaries between chemistry, biology, physics and maths.”

Tony leads a group at the Mechanobiology Institute in Singapore, focusing on dissecting the structure–function relationship that underlies protein complexes that are involved in cell migration and adhesion. He shares his thoughts on why you don’t necessarily have to choose between the different branches of science that you find fascinating.

We also feature interviews with first authors of a selection of papers published in Journal of Cell Science, helping early-career researchers promote themselves alongside their papers. Check out our recent First Person interview with Julia Abitbol.

The second in our series of cell dynamics meetings now turns to organelles. This May 2019 meeting in Lisbon, Portugal, aims to bring together scientists studying the interface between organelles and the cytoskeleton at different scales and perspectives using a range of model systems. Find out more and register your interest here.

We are currently seeking proposals for four Workshops to be held in 2020. Do you have an idea for a Workshop? Please let us know and you could be one of our 2020 Workshop organisers. You focus on the science, we focus on the logistics. We are particularly keen to receive proposals from postdocs. Deadline date for applications is 25 May 2018.

Meet the preLighters! In the latest interview with our preLights community, the preLights team caught up with James Gagnon, Assistant Professor at the University of Utah, to talk about his research, how science can be made more open, his enthusiasm for the preLights project and the fun sides of being a junior PI.

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Where could your research take you? Join Alexander and apply for the next round of Travelling Fellowships from JCS by 25 May 2018.